ZFS en ubuntu

IMPORTANTE: No lo recomiendo para entornos en producción.

Después de las pruebas realizadas y varios "kernel panics" he decidido no utilizarlo todavía en producción, es una lastima pero no me la juego.

Proceso de instalación de zfs:

# add-apt-repository "deb http://ppa.launchpad.net/zfs-native/stable/ubuntu oneiric main "
# aptitude update
# aptitude safe-upgrade -s
# aptitude install ubuntu-zfs

Creación del pool:

# zpool create cabina_emc /dev/mapper/mpath6-part1

Comprobamos el pool recién creado:

# zpool status -v
pool: cabina_emc
state: ONLINE
scan: none requested
config:

NAME STATE READ WRITE CKSUM
cabina_emc ONLINE 0 0 0
mpath6-part1 ONLINE 0 0 0

errors: No known data errors

Creamos un sistema de ficheros (dataset):

# zfs create cabina_emc/backup

Establecemos el punto de montaje:

# zfs set mountpoint=/media/cabina_emc cabina_emc
# zfs set mountpoint=/media/cabina_emc/backup cabina_emc/backup

Realizamos varias comprobaciones:

# zfs list
NAME USED AVAIL REFER MOUNTPOINT
cabina_emc 169G 838G 30K /media/cabina_emc
cabina_emc/backup 169G 838G 169G /media/cabina_emc/backup

# zfs mount cabina_emc/backup


# mount
cabina_emc/backup on /media/cabina_emc/backup type zfs (rw,xattr)

# df -h
S.ficheros Tam. Usado Disp. % Uso Montado en
cabina_emc/backup 1007G 169G 838G 17% /media/cabina_emc/backup

Listado de paquetes instalados:

# dpkg -l \*zfs*|grep iiii libzfs1 0.6.0.56-0ubuntu1~oneiric1 Native ZFS filesystem library for Linux
ii ubuntu-zfs 6~oneiric Native ZFS filesystem metapackage for Ubuntu.
ii zfs-dkms 0.6.0.56-0ubuntu1~oneiric1 Native ZFS filesystem kernel modules for Linux
ii zfsutils 0.6.0.56-0ubuntu1~oneiric1 Native ZFS management utilities for Linux

Solución de errores:

Si os aparece un error como este:
Apr 24 10:37:57 Mercurio kernel: [1018898.922590] vmap allocation for size 4198400 failed: use vmalloc= to increase size.

Editamos el  fichero: /etc/default/grub y añadimos el valor vmalloc.

# nano /etc/default/grub

# If you change this file, run 'update-grub' afterwards to update# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="vmalloc=512M"
GRUB_CMDLINE_LINUX=""

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

Actualizamos grub y reiniciamos el sistema:

# update-grub
# reboot

Comprobamos que el cambio surge efecto:

# cat /proc/meminfo
MemTotal: 2062236 kB
MemFree: 274552 kB
Buffers: 69436 kB
Cached: 1494816 kB
SwapCached: 12 kB
Active: 982260 kB
Inactive: 641228 kB
Active(anon): 46772 kB
Inactive(anon): 16796 kB
Active(file): 935488 kB
Inactive(file): 624432 kB
Unevictable: 47012 kB
Mlocked: 47012 kB
HighTotal: 1585096 kB
HighFree: 113960 kB
LowTotal: 477140 kB
LowFree: 160592 kB
SwapTotal: 1783144 kB
SwapFree: 1783132 kB
Dirty: 0 kB
Writeback: 0 kB
AnonPages: 106140 kB
Mapped: 16844 kB
Shmem: 1364 kB
Slab: 57488 kB
SReclaimable: 36392 kB
SUnreclaim: 21096 kB
KernelStack: 2232 kB
PageTables: 2916 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 2814260 kB
Committed_AS: 359632 kB
VmallocTotal: 524288 kB
VmallocUsed: 26680 kB
VmallocChunk: 281000 kB
HardwareCorrupted: 0 kB
AnonHugePages: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
DirectMap4k: 8184 kB
DirectMap2M: 503808 kB

Referencias:
http://hub.opensolaris.org/bin/download/Community+Group+zfs/docs/zfsadmin.pdf
http://zfsonlinux.org/faq.html
http://tech.libresoft.es/doku.php/manejozfs